This invention relates to apparatus and methods using one or more piezoelectric members for generating electricity from energy in a flowing stream of fluid. The need for such apparatus and methods has been recognized such as noted in U.S. Pat. No. 4,005,319 to Nilsson et al.; U.S. Pat. No. 4,387,318 to Kolm et al.; U.S. Pat. No. 4,595,856 to Glomb, Jr.; U.S. Pat. No. 5,512,795 to Epstein et al.; and U.S. Pat. No. 5,554,922 to Kunkel. There is still the need for such apparatus and method of an advantageous type suitable for use in-line within a fluid flow path inside a conduit. One specific need is within pipe or tubing in an oil or gas well in which a simple but dependable small power source is needed to power other downhole devices (e.g., a data acquisition device).